On my return from a short voyage to the north, I visited the coal field of New South Wales at Newcastle, on the Hunter. The beds are of vast extent, they lie upon the banks of a navigable river, and so near to the surface that the best qualities are raised, in a country of dear labor, at 8_s._ or 9_s._ the ton, and delivered on board ship for 12_s._ For manufacturing purposes the coal is perfect; for steamship use it is, though somewhat “dirty,” a serviceable fuel; and copper and iron are found in close proximity to the beds. The Newcastle and Port Jackson fields open a singularly brilliant future to Sydney in these times, when coal is king in a far higher degree than was ever cotton. To her black beds the colony will owe not only manufactures, bringing wealth and population, but that leisure which is begotten of wealth--leisure that brings culture, and love of harmony and truth. Manufactories are already springing up in the neighborhood of Sydney, adding to the whirl and the bustle of the town, and adding, too, to its enormous population, already disproportionate to that of the colony in which it stands. As the depot for much of the trade of Queensland and New Zealand, and as the metropolis of pleasure to which the wealthy squatters pour from all parts of Australia, to spend, rapidly enough, their hard-won money, Sydney would in any case have been a populous city; but the barrenness of the country in which it stands has, until the recent opening of the railroads, tended still further to increase its size, by failing to tempt into country districts the European immigrants. The Irish in Sydney form a third of the whole population, yet hardly one of these men but meant to settle upon land when he left his native island. In France there is a tendency to migrate to Paris, in Austria a continual drain toward Vienna, in England toward London. A corresponding tendency is observable throughout Australia and America. Immigrants hang about New York, Philadelphia, Boston, Sydney, Melbourne; and, finding that they can scrape a living in these large cities with toil somewhat less severe than that which would be needed to procure them a decent livelihood in the bush, the unthrifty as well as the dissipated throng together in densely-populated “bad quarters” in these cities, and render the first quarter of New York and the so-called “Chinese” quarter of Melbourne a danger to the colonies, and an insult to the civilization of the world.